Futures can and do change, something as simple as you're supposed to turn right down a street one day... In your bones u know it, and yet for reasons no one understands, you decide to debunk fate and go left. Now instead of meeting your spouse of your dreams and having a house full of kids, you get flattened by an ice-cream truck and spend the next 5 years in physical therapy recovering from the injuries; or worse you die from it. And all cause you exercised free will and turned the opposite way on a whim.